Power converters, including those configured to operate from DC power sources provided by vehicles and other DC power sources, may include what is commonly referred to as a cigarette lighter adapter (CLA). This CLA typically includes a DC/DC or AC/DC power converter configured to convert an input voltage of the power source to an output DC voltage suitable for powering a portable electronic device. This CLA may be configured to limit the voltage output and/or current output therefrom due to the needs of a device to be powered, and due to other safety and certification agency requirements.
Some CLA power adapters are also configured to be used in aircraft sockets provided proximate the passenger seats, allowing the passenger to power notebook computers, MP3 players and other portable electronic devices. Aircraft power sources typically provide a higher DC voltage such as 16-24 VDC, than provided by automobiles, such as 12-14 VDC. Due to safety concerns, and load balancing, there are requirements that CLA power adapters not be permitted to draw more than a predetermined power limit, such as 60 watts. Power systems deployed within the aircraft typically limit the amount of power that can be delivered to any one power socket accessible by the passenger. Some aircraft include safety mechanisms that will crowbar, or become deactivated, if a CLA attempts to draw more than 60 watts.
There is desired an improved power converter, such as a CLA power converter/adapter, that automatically limits power drawn from an aircraft power source to no more than a predetermined limit, such as 60 watts.